| A fluorescence SECOM platform can be integrated with any scanning electron microscope (SEM). (Image: Delmic BV) |
Pascal de Boer and Ben N. G. Giepmans of the University of Groningen (Groningen, Netherlands) and Jacob P. Hoogenboom of Delft University of Technology (Delft, Netherlands) have written a review in Nature Methods of the correlated light and electron microscopy (CLEM) technique, which combines both forms of microscopy to simultaneously examine biological cells.1 Hoogenboom is also cofounder of Delmic BV (Delft), one of the manufacturers of integrated microscopes mentioned in the work.
The paper highlights the rapid development and growth of CLEM. Previously, fluorescence and electron microscopy (EM) experiments on the same sample were performed sequentially; now, it is possible to perform these in integrated systems such as the SECOM platform made by Delmic.
The authors illustrate this with some work from Christopher Peddie and Lucy Collinson from Cancer Research UK. This shows integrated microscopy (using Delmic's SECOM platform) of resin-embedded HeLa cells expressing GFP-C1, a diacylglycerol sensor. The overlaid data shows excellent correlation between the fluorescence and EM images, clearly illustrating the power of using such techniques in the future. As the authors state, "CLEM adds resolution and cellular context to LM [light microscopy] observations and adds dynamics and target identification to EM observations. Experiments based on CLEM are beginning to provide insight in several biological contexts."
Development of the equipment is ongoing, including integrated microscopes (see figure) as well as large-scale and 3D EM and superresolution fluorescence microscopy.
REFERENCE:
1. Pascal de Boer, Jacob P. Hoogenboom, and Ben N. G. Giepmans, Nature Methods (2015); doi: 10.1038/nmeth.3400